It's purely my imagination, of course, that I feel the quiver of the deck plating as the shuttle settles on to it. I scold myself for watching the inboard camera intently as the shuttlebay repressurises, but for all my strictures my eyes don't move. I'm waiting to see my enemy, to see how he looks and how he acts (it almost certainly will be a 'he' – for all the Gender Equality stuff, I'd still bet my year's salary that when it comes to war, the bigwigs will opt for a man as the best choice). To see how he arrogantly surveys the territory he's come to take charge of, removing the onerous responsibility from the chap deemed unfitted to bear it now the chips are really down. Now that there's more weighing in the balance than the mere survival of Starfleet's flagship and the eighty-odd people on board her.

He's probably decided I can stay on in an 'advisory capacity'. Maybe he may need a few tips about the more arcane end of phase cannon operation one of the days, when he has nothing much better to do. In the meantime I can probably stay on the Bridge and look decorative while he takes over the reins of the really important stuff and places his rodents in the positions of authority.

I can't remember the last time I felt such boiling, impotent resentment. Well, yes, I can: the day that I told my father that I'd been accepted for officer training in Starfleet. Nothing mattered but the fact that it wasn't the Navy. As if I hadn't fucking torn my guts out working to get into the sodding Navy. As if it hadn't ripped my heart out when I was told I'd failed solely because of my phobia of drowning, a phobia I'd fought tooth and nail to conquer, but not, it seemed, quite hard enough. As if I hadn't clung to the desperate hope that even though it wasn't the Navy, acceptance into a coveted élite like Starfleet's officer class might count for something; might win me some kind of grudging forgiveness.

I don't know what bloody planet I was on when I thought that fairy story up. I wasn't good enough for the Navy. That was all that mattered. I'd finally produced the absolute, damning proof that I was the failure he'd always thought I would be. I wasn't just a runt and a weakling, I was a coward to boot. I wasn't fit to bear the proud name of Reed, and nothing, nothing, I could ever achieve in this life would ever make amends for that.

"Are you okay, sir?"

I've plunged so far back into the past that the soft question makes me jump. I hadn't even noticed Hoshi leave her station and walk across to me. I'd thought she was thoroughly immersed in her work on the linguistics database upgrades, but it seems not. I look down at my right fist, clenched so hard where it's resting beside the long-range scanner that the knuckles are completely bloodless, and I can guess that my face has gone pale too, blanched with pain and anger.

This is not professional behaviour. With an effort, I will my fist to unclench. The fingers move slowly; they seem to have been rigid for some considerable time. I draw several calming breaths, willing my temper to subside. Anger can't always be overcome, but with the appropriate discipline it can always be channelled – a process far more productive than allowing it to spill over into pointless spitting and yowling, which ultimately achieves nothing.

When I'm sure I have my face and voice under control, I look back at Hoshi. It's considerate of her to have come and asked me quietly, not making a big thing of it in front of the support staff who are busy checking the readings as the ship's system runs a full schedule of tests. She's a lovely young woman and a good friend, and if things were different I suspect I'd trust her with a lot of things that I'd confide to very few people indeed. But if wishes were horses, as the old saying goes, and old habits die hard. And I learned long ago that trust is a treacherous thing, only marginally less so than hope, and so I nod and fish up a faint smile from somewhere. "I'm just glad the captain's back with us, Ensign," I say, lying as effortlessly as I can when I need to. "Maybe it's a sign we're nearly ready to get on with the mission."

I'm not altogether sure she buys it. Her intelligent brown eyes remain troubled, though I meet them steadily. But at a guess she knows she won't get any more from me, because she nods and goes back to her station, and moments later T'Pol leans over and asks a question, and the two of them become immersed in some technical issue. And I, unnoticed, breathe out a long, soundless sigh of relief.

"Archer to Lieutenant Reed."

Well, it's not like I haven't been expecting the summons. The advent of that troop transport plus the presence of three unannounced additional personnel aboard the shuttle add up to everything bar certainty in my mind. And I suppose I can understand the seductive allure to the captain of having 'professional soldiers' on board, rather than gifted amateurs who've slogged their bollocks off to come up to the standards I've demanded of them; though deep inside me, it still feels like a betrayal. Still, that's something I'll have to come to terms with, as and if I can. Much will depend on the calibre of this interloper he's bringing on board, and that has yet to be revealed.

In the meantime, another deep breath enables me to settle the mask more securely into place.

"Reed here, sir."

"I'd like you to meet me down at the launch bay, Lieutenant. I have a few introductions to make."

"Sir." I close the link and rise obediently, the very model of a perfectly disciplined Starfleet officer. My steps to the turbo-lift are neither hurried nor slow. I enter the compartment and press the required button briskly. Muscle by muscle, as the lift descends to G Deck, I compose my face into the quiet, attentive expression of a subordinate accepting a directive from a superior officer. I'll say 'Yes sir' and 'Welcome aboard sir' and 'Pleased to meet you, sir', and not even Hoshi would pick up the feeling behind it. Certainly the captain won't. As for the MACO, I don't suppose he'll give a flying fuck if I'm pleased or not. Not that he'll know. The old Navy maxim run silent, run deep was a very good one for me as a Section operative, and I'll run so silent and so deep now he's on board that he'll hardly know I exist. That was what the old nuclear subs used to do, in the days before World War Three: cruise submerged down in the total darkness, with a payload on board that could flatten a continent.

Not that I'm out to cause trouble in any way. The mission depends on all of us co-operating, and a Reed does not endanger any mission for the sake of hurt pride. He'll find nothing to complain of when his attention turns in my direction, I'll make sure of that. But there are many levels of co-operation, and the interloper had better not make the mistake of thinking that friendship will be among the added extras on offer.

Just as I'm about to emerge from the turbo-lift, the comm unit springs to life. "Sato to Lieutenant Reed."

I hesitate. The last thing I want to do is give the Head Rat an excuse to write me down as tardy in obeying an order from the captain, but Hoshi knows where I'm headed, and she wouldn't call me if it wasn't urgent. I step to the unit and thumb the button. "Reed."

Her voice has a note of anxiety in it. "Sir, there's a data-package come from Earth for your attention. It's marked urgent, but it's been delayed. They say there was some kind of problem with the transmission and nobody noticed."

My mouth tightens. Bloody HQ efficiency. "Thank you, Ensign. Route it to my station and I'll deal with it as a priority on my return. Reed out."

I've only lost a couple of seconds, and at least now I can concentrate on the opening gambit on this game of real-life chess. Most games are won and lost in the first few moves. He'll make the opening play, I'll see to that. And then the available responses will be laid out for me to choose among. I play the computer most nights, and a lot of the time I win. Strategy and tactics, Ratty, strategy and tactics.

Longer strides make up for the lost few seconds. I straighten my uniform, straighten my back. He won't see a damn thing I don't want him to see.

The door hisses open. Four people have climbed out of the shuttle – the pilot, presumably, is still inside, waiting till the launch bay empties and depressurises again so he can return to Jupiter Station. One of them is the captain. Two of the others might as well be Laurel and Hardy for all I notice them. My gaze has flown to the Head Rat, the man who's come to take over the position in which I've taken so much pride. And there it stops.

Time rolls back. His finger, pointing; his voice, slurred with red wine. "I know you're not really there. But if you want it..."

The hair stands up on the back of my neck. It literally does. My hackles. I swear to God, if my survival hung on my being able to describe exactly what I feel in this instant, I'd order the funeral right now. I want to fly across the room and butter him all over the walls; I want to throw him down on the floor, rip his kit off and suck him halfway to paradise before I fuck him the rest of the way. And those are the simple whole effect is, quite simply, indescribable.

He knows. I'd swear he knows. There's something ... something beyond the summing stare I expect from a man who's here to take my hard-won place.

"Captain," I say politely, transferring my gaze to my CO after the barest pause.

Captain Archer speaks slightly louder than usual, probably anticipating some resistance to the concept on my part and determined to override it. "Lieutenant, let me introduce you to Major Matthew Hayes. General Casey has kindly lent us a squad of his top MACOs for the mission."

"Major." My voice is civil. Totally civil. Totally bland. I meet his eyes again with the cool, open stare of a stranger.

"Lieutenant." Oh bugger, another Yank who can't pronounce Lieutenant properly. At least his accent's not as bad as Trip's. Perversely, this last fact irks me, as though it would be less annoying if he sounded like the 'down home country-boy' I mistakenly thought Trip was when I first came on board. That said, merely the fact that he's breathing is a source of irritation to me right now. Though the really infuriating bit is the realisation that as a major he outranks me, and my fate is now officially sealed.

"Corporal Chang, Corporal McKenzie," he continues, indicating Laurel and Hardy, presumably two of his subordinate rats. "The rest of the squad are following on under the command of Sergeant Kemper. They're scheduled to arrive at eighteen hundred hours, just before the launch."

Oh, nice. He's barely set foot on the decking and he already knows more about the bloody ship's schedule than I do! I acknowledge the junior officers' existence with a brief nod, to which they respond appropriately – just as well for them.

The captain has waited for us all to do the polite stuff, and then picks up the conversation again. "The General and I have decided that since you have ship-board experience, Lieutenant, for the purposes of the mission you should be considered to be the senior officer. Major Hayes is already aware of this. Though I'm sure you'll take any of his opinions under advisement."

A quick mental scan of the regulations finds no specific reference as to the impropriety of dancing the fandango around the shuttlebay in the presence of your commanding officer, but I contain myself nevertheless.

"Certainly, sir. Thank you," I say politely.

"I hope we'll establish a good working relationship, Lieutenant," says Major If-You-Want-It.

"I hope so too, Major," I say politely. Would that be with or without an inadvisable quantity of red wine and a cognac or two?

"If there's anything you need to discuss in the information about my team, I'm at your disposal. Sir," he adds, with a commendable lack of irony at having to address an officer whom he technically outranks by that title.

I return his gaze blankly, and then allow a look of inspiration to dawn. "Information? Oh, yes. Our communications officer has just advised me that a high-priority data package for me arrived just after your shuttle did. It had been accidentally delayed, apparently. I dare say that's the information you're referring to."

A look of unmistakable discomfiture. It's not his fault, but he knows damn well it doesn't look good for his bloody MACOs and their inefficient admin. Not a good start – not a good start at all.

"Then you weren't expecting our arrival, sir." It's a statement rather than a question. "I apologize for that."

I'm already turning away, ostensibly to open the door for the captain – who's preparing to leave me to play nicely with my new little friends – but at this I look back. "No, Major, unfortunately I wasn't. But I know these things happen in even well-run departments. I'm sure we both expect high standards on board ship."

The captain knows me well enough to give me a somewhat searching stare at that, but there's absolutely nothing in it that he can reasonably take exception to. So he orders me to pass on the information about our new arrivals to the quartermaster, who'll have the task of finding somewhere for all the rats to nest during the voyage (my description, not the captain's). It's probably just as well that he leaves before Ensign Wilcox responds to the message I leave with one of his staff to contact me, because in the face of having this little lot dumped on him out of the blue, our quartermaster's private opinions will probably be almost as colourful as mine – and he's had a lot less experience in hiding it over a comm link.

That leaves me and the MACOs in the shuttlebay. I suggest that it might be a good idea for us to leave, because the lights have come on to signal the shuttle is cleared to go as soon as the area is emptied and sealed. Being sucked out into hard vacuum is not in accordance with health and safety regulations, and I had a memorable conversation with Trip back on Shuttlepod One on the feasibility of holding one's breath for an improbable length of time. Strictly speaking, whoever's manning the control booth should run the safety checks before starting depressurisation, but in the case of a failure on someone's part to adhere to that particular part of the process there would be certain difficulties involved with any of us lodging a complaint about it afterwards.

I still haven't decided whether or not he's recognised me. I'm pretty sure he has, but I don't know him nearly well enough to be able to tell if his voice is normal or not. This is where Hoshi's talents would come in handy, but it would be a delicate sort of thing to phrase if I were to ask for her help. I can imagine it stopping quite a few nearby conversations if I embarked on the explanation in the Mess Hall. By the time I got to the grand finale, you'd probably be able to hear a pin drop.

The door to the shuttlebay closes behind us. The three MACOs have their personal belongings; presumably the rest of their things will be following on in the troop transport. They stand waiting to be told where to go.

I look at them impassively.

"In view of the fact we had no notice of your arrival, I think it's best you use the guest quarters until our Quartermaster makes his disposals," I observe. "I'll take you there. I recommend you use the terminals in your rooms to acquaint yourselves with ship routine – you should be able to access all basic visitor information. As soon as I've had time to look through your vetting data I'll add you to the appropriate security protocols."

"I'd appreciate that, Lieutenant," says Hayes evenly.

We walk to the guest quarters on G Deck in silence. Fortunately the ship's designers envisaged that we might need a decent bit of spare accommodation; most of it will probably be allocated to the higher-ranking MACOs, and at a guess the rest will be billeted out among the crew. Not the officers, though, with any luck. Dear Lord, not the officers. Don't let Captain Sensible come up with the idea that as we're both weapons specialists it would be a good idea for Hayes and me to share a room, because we'd have so many items of mutual interest to talk about in the shift-change intervals. There'd be murder done before we passed Pluto.

The two corporals can share a room until Ensign Wilcox makes his dispositions, and I point them to a suitable one. Hayes as their CO can have his own; I owe his rank that much.

The silence as the two of us walk the few metres to his new quarters is as thick as treacle. I suspect he's waiting (hoping?) for me to say something, but I'll be damned if I will.

I'm perfectly well aware that if I tell Em any of this she'll come out with a string of Spanish obscenities and finally tell me I'm behaving like a petulant child. (Her absolute respect for my authority has never, ever, stopped her from mentioning the fact that that I'm behaving like a total prick whenever she feels this is the case. Fortunately for me, she does this in private, and even more fortunately, it doesn't happen very often.) She'd probably be right, at that, but just at this moment I don't give a shit. Too many things have rushed back over me with too little warning, and I'm going to need time to make the appropriate adjustments. Until then, the silence can stay just where it is.

And if Major Matthew Hayes has anything he particularly wants to say, that's up to him. But if he chooses to venture into the dragon's cave, he'd better be wearing some damn thick fire-retardant underwear. He did more damage to me than practically anyone else I can remember in my adult life, and I'm not in a forgiving mood.

We reach the door. I'm sure he doesn't need me to hit the access button for him.

The door hisses back. He hesitates for just a second, while I stare back at him stonily. He does recognise me. I'm sure of it. But if there was ever anything between us, I've forgotten it completely.

"The morning briefing is in the captain's Ready Room on the Bridge at zero eight hundred hours," I say into the small, hollow pause. "As tomorrow will be your first day he'll probably want to introduce you to the other senior officers. Until then, consider yourself off duty. Until I clear your security access, you're to consider Main Engineering and the Armoury as off limits, and do not attempt to access the Bridge until zero seven fifty-five tomorrow morning at the earliest.

"Dismissed."

"Sir," he says quietly. And, clearly knowing it's completely against the rules to continue a conversation his superior officer has terminated, he walks into the room and shuts the door.

I'm left looking at the blank sheet of duranium.

There isn't a single word I've said to him that's one I wouldn't say to any new member of the crew who'd come aboard without the standard security clearance. As Head of Security, I could and would say it to a bloody Admiral who'd happened to sneak on board under the radar. There isn't a disciplinary tribunal in Starfleet which wouldn't dismiss all charges and let me walk out of court without a stain on my character if I was hauled up before it for improper conduct. I was clear, I was precise, I was objective, I was polite. I've been a perfect professional from start to finish.

So why the hell do I feel so furious with myself?

My shift ends in half an hour. I ought to return to the Bridge, but I'm not sure I can be trusted with the live firing mechanism just now. Instead I make my way to the Armoury, where I run simulations that light up the display like the Fifth of November, hammering hell out of the firing sequences until Bernhard coughs respectfully behind me.

"Herr Leutnant, your shift ended an hour ago," he informs me somewhat hesitantly. "I think you may perhaps have forgotten the time..."

I look at the screen, where CG images of beautiful symmetrical explosions dissipate slowly. My hit ratio's even better than usual, and I'd set the difficulty ratio to maximum. Apparently anguish is good for the aim.

I should change into civvies and head for the Mess Hall, but I'm not hungry. Instead, as soon as I'm out of the shower I drag on my sports gear and head for the gymnasium. There's a punch-bag there with which I have an urgent appointment.

And the problem of Major Matthew Hayes can wait until tomorrow.